In recent years, speeding up of a data rate has been advanced so as to transmit a large volume of data by one signal, along with increase of a data communication amount in a field of communication. With this speeding up, a circuit which meets a high speed for amplifying, shaping, and driving a high-speed signal is demanded. As an amplifier circuit for amplifying a signal, a grounded-emitter amplifier circuit, a differential grounded-emitter amplifier circuit thereof, and the like are widely used. In these amplifier circuits, parasitic capacitances of collector of a transistor, a wiring, an additional circuit, and the like cause deterioration of a band, an insufficient frequency property (lack of a high frequency range), and insufficient rising/falling in an eye waveform, and jitter increase, bringing difficulty in speeding up.
A feedback type high-speed amplifier circuit (refer to FIG. 2 of Justin Abbott, Calvin Plett, John W. M. Rogers, “A 15 GHz, 1.8V, Variable-Gain, Modified Cherry-Hooper Amplifier”, IEEE 2005 CUSTOM INTEGRATED CIRCUITS CONFERENCE, 22-5-1 to 22-5-4, p.645 to p.648, for example) has been disclosed as a speeding-up measure. This circuit subtracts low-speed components from a signal by a feedback circuit so as to realize a wider bandwidth and speeding up.
However, even in the feedback type high-speed amplifier circuit, a parasitic capacitance of the added feedback circuit further causes deterioration of a band and jitter increase, bringing difficulty in realizing sufficient speeding up. A factor interfering the speeding up is increase of a parasitic capacitance caused by a feedback circuit (C2 in a formula (5) in Justin Abbott, Calvin Plett, John W. M. Rogers, “A 15 GHz, 1.8V, Variable-Gain, Modified Cherry-Hooper Amplifier”, IEEE 2005 CUSTOM INTEGRATED CIRCUITS CONFERENCE, 22-5-1 to 22-5-4, p.645 to p.648). Especially, a base parasitic capacitance of a transistor of the feedback circuit is the main factor of deterioration. Further, the speeding up is performed by performing subtraction from a main signal by a feedback circuit. However, not only low-speed components but also high-speed components are subtracted in this configuration. Therefore, the high-speed components are further deteriorated, causing difficulty in realizing of a wider bandwidth and speeding up.